SUPPLEMENTAL GUARANTOR FINANCIAL INFORMATION (Statements of Operations) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended			110 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019
Supplemental Guarantor Financial Information Statement of Operations [Line Items]
Sales	$ 1,387.1	$ 1,576.6	$ 1,592.9	$ 1,553.4	$ 1,635.0	$ 1,872.4	$ 1,728.4	$ 1,710.3	$ 6,110.0	$ 6,946.1	$ 6,268.4
Cost of goods sold	1,270.6	1,357.6	1,463.7	1,347.3	1,391.0	1,441.7	1,460.7	1,528.7	5,439.2	5,822.1	5,554.9
Selling and administration									416.9	430.6	369.8
Restructuring charges									76.5	21.9	37.6	$ 285.6
Acquisition-related costs									0.0	1.0	12.8
Other operating (expense) income									0.4	6.4	3.3
Operating (loss) income									(177.8)	(676.9)	(296.6)
Earnings (losses) of non-consolidated affiliates									0.0	(19.7)	1.8
Equity income in subsidiaries									0.0	0.0	0.0
Interest expense									243.2	243.2	217.4
Interest income									1.0	1.6	1.8
Non-operating pension income (expense)									16.3	21.7	34.4
Other income									11.2	0.0	0.0
Income (loss) before taxes									(36.9)	437.3	117.2
Income tax (benefit) provision									(25.6)	109.4	(432.3)
Net (loss) income	$ (77.2)	$ 44.2	$ (20.0)	$ 41.7	$ 53.3	$ 195.1	$ 58.6	$ 20.9	(11.3)	327.9	549.5
Parent Guarantor
Supplemental Guarantor Financial Information Statement of Operations [Line Items]
Sales									1,340.6	1,423.8	1,330.3
Cost of goods sold									1,210.4	1,153.1	1,195.5
Selling and administration									211.0	206.0	157.0
Restructuring charges									1.4	0.0	1.7
Acquisition-related costs										1.0	12.8
Other operating (expense) income									(16.2)	(3.0)	(11.1)
Operating (loss) income									98.4	(60.7)	47.8
Earnings (losses) of non-consolidated affiliates										(19.7)	1.8
Equity income in subsidiaries									96.9	310.7	638.4
Interest expense									94.5	68.6	44.5
Interest income									5.4	5.8	6.3
Non-operating pension income (expense)									22.2	26.6	38.5
Other income									11.2
Income (loss) before taxes									(57.2)	315.5	592.7
Income tax (benefit) provision									(45.9)	(12.4)	43.2
Net (loss) income									(11.3)	327.9	549.5
Issuer
Supplemental Guarantor Financial Information Statement of Operations [Line Items]
Sales									0.0	0.0	0.0
Cost of goods sold									0.0	0.0	0.0
Selling and administration									0.0	0.0	0.0
Restructuring charges									0.0	0.0	0.0
Acquisition-related costs										0.0	0.0
Other operating (expense) income									0.0	0.0	0.0
Operating (loss) income									0.0	0.0	0.0
Earnings (losses) of non-consolidated affiliates										0.0	0.0
Equity income in subsidiaries									66.6	289.6	357.6
Interest expense									136.2	153.3	165.8
Interest income									0.0	0.0	0.0
Non-operating pension income (expense)									0.0	0.0	0.0
Other income									0.0
Income (loss) before taxes									(69.6)	136.3	191.8
Income tax (benefit) provision									(32.4)	(35.1)	(310.0)
Net (loss) income									(37.2)	171.4	501.8
Subsidiary Non-Guarantor
Supplemental Guarantor Financial Information Statement of Operations [Line Items]
Sales									5,239.7	5,937.0	5,344.9
Cost of goods sold									4,699.1	5,083.7	4,766.2
Selling and administration									205.9	224.6	212.8
Restructuring charges									75.1	21.9	35.9
Acquisition-related costs										0.0	0.0
Other operating (expense) income									16.6	9.4	14.4
Operating (loss) income									(276.2)	(616.2)	(344.4)
Earnings (losses) of non-consolidated affiliates										0.0	0.0
Equity income in subsidiaries									0.0	0.0	0.0
Interest expense									20.5	26.9	13.0
Interest income									3.6	1.4	1.4
Non-operating pension income (expense)									(5.9)	(4.9)	(4.1)
Other income									0.0
Income (loss) before taxes									253.4	585.8	328.7
Income tax (benefit) provision									52.7	156.9	(165.5)
Net (loss) income									200.7	428.9	494.2
Eliminations
Supplemental Guarantor Financial Information Statement of Operations [Line Items]
Sales									(470.3)	(414.7)	(406.8)
Cost of goods sold									(470.3)	(414.7)	(406.8)
Selling and administration									0.0	0.0	0.0
Restructuring charges									0.0	0.0	0.0
Acquisition-related costs										0.0	0.0
Other operating (expense) income									0.0	0.0	0.0
Operating (loss) income									0.0	0.0	0.0
Earnings (losses) of non-consolidated affiliates										0.0	0.0
Equity income in subsidiaries									(163.5)	(600.3)	(996.0)
Interest expense									(8.0)	(5.6)	(5.9)
Interest income									(8.0)	(5.6)	(5.9)
Non-operating pension income (expense)									0.0	0.0	0.0
Other income									0.0
Income (loss) before taxes									(163.5)	(600.3)	(996.0)
Income tax (benefit) provision									0.0	0.0	0.0
Net (loss) income									$ (163.5)	$ (600.3)	$ (996.0)